Search results for "Butanol"
showing 10 items of 71 documents
The combined effect on initial glucose concentration and pH control strategies for acetone-butanol-ethanol (ABE) fermentation by Clostridium acetobut…
2021
Abstract The use and depletion of fossil fuels raised the interest in biofuels like biobutanol. Clostridium acetobutylicum DSM 792 is capable of producing biobutanol through ABE fermentation. Butanol production can be influenced by low sugar concentrations, like those obtained after hydrolysis of pre-treated lignocellulosic biomass. This study aimed to evaluate the influence of the initial glucose concentrations (33, 66 and 100 g L−1) and pH control strategies on biobutanol production and glucose consumption. Uncontrolled pH fermentation exhibited low butanol production due to either glucose exhaustion (33 g L−1) or the phenomenon of acid crash (66 and 100 g L−1), which was alleviated by th…
Bioconversion of amino acids into flavouring alcohols and esters by Erwinia carotovora subsp. atroseptica
1991
International audience; Erwinia carotovora subsp. atroseptica produced flavour compounds when infecting endives (Cichorium intybus). These compounds were identified as esters and branched-chain alcohols.They were produced from amino acids and some of them such as methionol, methionol acetate, isobutanol, isobutyl acetate, beta-phenyl ethanol and tryptophol were produced with good yields.
The individual contribution of starter and non-starter lactic acid bacteria to the volatile organic compound composition of Caciocavallo Palermitano …
2017
Abstract The contribution of two starter ( Lactobacillus delbrueckii and Streptococcus thermophilus ) and nine non-starter ( Enterococcus casselliflavus , Enterococcus faecalis , Enterococcus durans , Enterococcus gallinarum , Lactobacillus casei , Lactobacillus paracasei , Lactobacillus rhamnosus , Pediococcus acidilactici and Pediococcus pentosaceus ) species of lactic acid bacteria (LAB) to the volatile organic compounds (VOCs) of Caciocavallo Palermitano cheese was investigated. The strains used in this study were isolated during the production/ripening of the stretched cheese and tested in a cheese-based medium (CBM). The fermented substrates were analyzed for the growth of the single …
Six-Step Gram Scale Synthesis of the HIV Integrase Inhibitor Dolutegravir Sodium
2021
A short and practical synthesis for preparing the active pharmaceutical ingredient dolutegravir sodium was investigated. The convergent strategy developed herein starts from 3-(R)-amino-1- butanol and builds up the BC ring system in 76% isolated yield over four steps. Ring A was constructed by a one-pot 1,4-addition to diethyl-(2E/Z)-2-(ethoxymethylidene)-3-oxobutandioate and subsequent MgBr2·OEt2-mediated regioselective cyclization. Amide formation with 2,4- difluorobenzylamine was either performed from the carboxylic acid or through aminolysis of the corresponding ester precursor. Final salt formation afforded dolutegravir sodium in 48–51% isolated yield (HPLC-purity: 99.7–99.9%) over six…
Isobaric Vapor−Liquid Equilibria for Binary and Ternary Mixtures of Diisopropyl Ether, 2-Propyl Alcohol, and 3-Methyl-1-Butanol
2008
Consistent vapor−liquid equilibrium data for the binary and ternary systems diisopropyl ether (1) + 2-propyl alcohol (2) + 3-methyl-1-butanol (3) are reported at 101.3 kPa. The diisopropyl ether (1) + 3-methyl-1-butanol (3) system shows positive deviations from ideal behavior, and the 2-propyl alcohol (2) + 3-methyl-1-butanol (3) system exhibits slight deviations from ideal behavior. The activity coefficients and the boiling points were correlated with their compositions by the Wilson, NRTL, UNIQUAC, and Wisniak−Tamir equations. It is shown that these models allow a very good prediction of the phase equilibria of the ternary system using the pertinent parameters of the binary systems. 3-Met…
Isobaric Vapor−Liquid Equilibria of Trichloroethylene with 1-Butanol and 2-Butanol at 20 and 100 kPa
1996
Vapor−liquid equilibria for trichloroethylene + 1-butanol, and + 2-butanol are reported at 20 and 100 kPa. The two systems satisfy the point-to-point thermodynamic consistency test. Both systems show a positive deviation from ideality.
Vapor−Liquid Equilibria for the Binary Systems Isobutanol with m-Xylene, o-Xylene and p-Xylene at 101.3 kPa
1999
Vapor−liquid equilibria were measured for binary systems of isobutanol with m-xylene, o-xylene, and p-xylene at 101.3 kPa using a recirculating still. The accuracy of experimental measurements was ±0.1 K in temperature, ±0.01 kPa in pressure, and ±0.001 in mole fraction. The results were determined to be thermodynamically consistent according to the point-to-point consistency and Wisniak tests. All the systems show moderate positive deviations from ideality. The data were correlated with five liquid-phase activity coefficient models (Margules, Van Laar, Wilson, NRTL, UNIQUAC).
Enhancing effect of alpha-hydroxyacids on "in vitro" permeation across the human skin of compounds with different lipophilicity.
2005
The percutaneous penetration-enhancing effects of glycolic acid, lactic acid and sodium lauryl sulphate through the human epidermis was investigated using 5-fluorouracil as a hydrophilic model permeant and three compounds belonging to the phenylalcohols: 2-phenyl-ethanol, 4-phenyl-butanol and 5-phenyl-pentanol. The lipophilicity values of the compounds ranged from log Poct -0.95 to 2.89. The effect of the enhancer concentration was also studied. Skin pretreatment with aqueous solutions of the three enhancers did not increase the permeability coefficient of the most lipophilic compound (log Poct = 2.89). For the other compounds assayed, the increase in the permeability coefficients depended …
Mass action model for solute distribution between water and micelles. Partial molar volumes of butanol and pentanol in dodecyl surfactant solutions
1986
The densities of 1-butanol and 1-pentanol were measured in aqueous solutions of dodecyltrimethylammonium bromide and dodecyldimethylamine oxide and the partial molar volumes at infinite dilution of the alcohols in aqueous surfactants solutions were obtained. The observed trends of this quantity as a function of the surfactant concentration were rationalized using a mass-action model for the alcohol distribution between the aqueous and the micellar phase. At the same time, the model was revised to account for the alcohol effect on the surfactant micellization equilibrium. The partial molar volume of alcohols in the aqueous and in the micellar phases and the ratios between the binding constan…
Possible Fungistatic Implications of Betulin Presence in Betulaceae Plants and their Hymenochaetaceae Parasitic Fungi
2010
Betulin and its derivatives (especially betulinic acid) are known to possess very interesting prospects for their application in medicine, cosmetics and as bioactive agents in pharmaceutical industry. Usually betulin is obtained by extraction from the outer layer of a birch bark. In this work we describe a simple method of betulin isolation from bark of various species of Betulaceae trees and parasitic Hymenochaetaceae fungi associated with these trees. The composition of the extracts was studied by GC-MS, whereas the structures of the isolated compounds were confirmed by FTIR and 1H NMR. Additionally, the significant fungistatic activity of betulin towards some fi lamentous fungi was deter…